WASHINGTON — The State Department issued a dismal assessment of Iran’s record on human rights on Thursday, hours before Secretary of State John Kerry was to leave for Vienna to try to conclude a nuclear accord with Tehran.

“The government arrested students, journalists, lawyers, political activists, women’s activists, artists and members of religious minorities, many with crimes such as ‘propaganda against the system,’ ” the report said. It added, “The government and its agents reportedly committed arbitrary or unlawful killings, including, most commonly, by execution after arrest without due process.”

This is the second time in two weeks that the State Department has asserted that Iran’s policies do not appear to have substantially changed since Hassan Rouhani was elected president in 2013. Last week, the State Department said that Iran was still involved in “terrorist-related” activities, and that it was providing broad military support to President Bashar al-Assad of Syria.

The expected nuclear deal has stoked a heated debate: Will the nuclear agreement be the first step in a long process that will lead to regional cooperation between the United States and Iran and less repression by Tehran? Or will such a deal provide Iran with billions more in funds to pursue an aggressive foreign policy while it represses dissent at home?

At a minimum, the State Department report indicates how far Iran needs to go to meet the concerns of human rights advocates. Tom Malinowski, the assistant secretary of state for human rights, said there had been no discernible progress on Iran’s record on human rights since Mr. Rouhani became president.

“I can’t say that we have seen any meaningful improvement in the human rights situation in Iran,” he said at a news briefing.

Surveying human rights around the world, the new report, not surprisingly, assailed longtime human rights violators like Syria and North Korea. But another theme of the report was that participation in the American-led coalition against the Islamic State does not mean that the United States’ partners should be unaccountable for human rights abuses at home.

“In Saudi Arabia, peaceful Internet activist Raif Badawi was sentenced to 10 years in prison and 100 lashes by a court originally set up to try terrorists,” Mr. Malinowski said.

“Egypt has used a real threat of terrorism to justify the prosecution of nonviolent opposition figures, human rights activists and demonstrators,” he added. “Bahrain has a legitimate interest in protecting its people against violent groups, yet its government has focused much of its energy on prosecuting peaceful critics, including this year opposition leader Sheikh Ali Salman.”

In Kuwait, the report says, a man named Abdullah Fayrouz was sentenced to five years in prison, followed by permanent exile, for “defaming the emir” via Twitter.

Mr. Kerry, who entered the State Department briefing room on crutches following an accident last month in which he broke his leg, said that the report contained “a vast amount of objective research.”

He acknowledged that some countries with whom the United States has close relations could be expected to object to the report’s findings. But he said that his advice to any leaders who were unhappy with the report’s conclusions was to examine their own countries’ human rights practices.

“The way to alter what the world thinks and the way to change these judgments is to alter what is happening in those countries,” Mr. Kerry said.

He said that the United States was not without its own human rights failings, including a record of racial discord and unrest. “There is zero arrogance,” he said.

But some critics said the United States often did not give enough weight to its own human rights findings. “The larger problem is that the U.S. government too often disregards these reports’ findings in formulating U.S. foreign policy,” said John Sifton, an advocate at Human Rights Watch.

The report provided a bleak appraisal of the human rights record in China, whose senior officials met this week with Mr. Kerry and Treasury Secretary Jacob J. Lew in Washington. And it took note of a crackdown on political opposition by President Vladimir V. Putin of Russia.

“Russia’s political system is increasingly authoritarian, and the government instituted a range of new measures to suppress dissent within its borders,” the report said.

Vietnam, it said, maintains “severe” restrictions on its citizens’ political rights. Human rights amendments to Vietnam’s constitution have yet to be put into effect. The coup in Thailand has led to a severe limitation on civil liberties. In Myanmar, the report added, human rights abuses against Muslims in Rakhine State remain a “severely troubling counterpoint to the broader trend of progress since 2011.”

The section on Cuba is likely to receive attention in light of the Obama administration’s push to improve relations with Havana. The United States and Cuba are expected to formally open embassies in each other’s capitals next month, and the Obama administration has asserted that the renewed ties will put it in a stronger position to lobby for political reform there.

Mr. Malinowski said that Cuba had released the “vast majority” of the political prisoners who have drawn international attention. But he said that short-term arrests, which the Cuban government has used to harass its political opponents, had continued. Though the number of such short-term arrests declined earlier this year, it has increased in the past few months.

“This is a problem that continues,” he said.

A version of this article appears in print on , on Page A3 of the New York edition with the headline: State Dept. Human Rights Report Assails Iran . Order Reprints | Today’s Paper | Subscribe